问题描述
我正在研究使用Spring Data的项目。我想使用 @CreatedDate 注释填写 creationTime 字段，而不是使用 @PreUpdate 或 @PrePersist 注释（以这种方式完美地运行）。当我使用 @CreatedDate 执行此操作时，它只会将此字段留空。我使用postgresql数据库。 不是很有帮助。
I am working on project where I use Spring Data. I wanted to fill in creationTime field using @CreatedDate annotation instead using method with @PreUpdate or @PrePersist annotation (doing it this way it works perfectly). When I do it with @CreatedDate it just leaves this field blank. I use postgresql database. Documentation is not very helpful.
您有什么想法我该如何解决？谢谢！
Do you have any idea how can I fix it? Thank you!
import org.springframework.data.annotation.CreatedDate;
@Entity
@Table(name = "software")
public class Software implements Serializable {
// ...
@Column(name = "creation_time")
@CreatedDate
private Date creationTime;
//...
}
我的 applicationContext ：
<jpa:repositories base-package="path.to.dao"/>
<context:component-scan base-package="path.to.dao"/>
<context:property-placeholder location="classpath:application.properties"/>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${db.driver}"/>
<property name="url" value="${db.url}"/>
<property name="username" value="${db.username}"/>
<property name="password" value="${db.password}"/>
</bean>
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="packagesToScan" value="path.to.bean"/>
<property name="dataSource" ref="dataSource"/>
<property name="jpaVendorAdapter" ref="jpaAdapter"/>
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
<prop key="hibernate.format_sql">${hibernate.format_sql}</prop>
<prop key="hibernate.ejb.naming_strategy">${hibernate.ejb.naming_strategy}</prop>
<prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
</props>
</property>
</bean>
<bean id="jpaAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>
推荐答案
我可能一直处于类似的情况，我希望Spring Data JPA @CreatedDate 注释可以工作，但是不需要进行用户级审计否则在他们的文档中描述。
I may have been in a similar situation where I wanted the Spring Data JPA @CreatedDate annotation to work, but had no need for the user-level auditing that is otherwise described in their documentation.
为了让基于注释的审计工作，我不得不在我的项目中添加一个实现 org的类.springframework.data.domain.AuditorAware 。这很奇怪，因为您实际上似乎并没有使用您将要实现的 getCurrentAuditor（）方法返回的值;我只返回 null 。
To get the annotation-based auditing to work, I had to nonetheless add a class to my project that implemented org.springframework.data.domain.AuditorAware. This is odd because you don't actually seem to use the value returned from the getCurrentAuditor() method that you'll be implementing; mine just returns null.
public class NullAuditorBean implements AuditorAware {
@Override
public Object getCurrentAuditor() {
return null;
}
}
然后我需要引用我的空对象 AuditorAware 在我的 applicationContext 的条目中实现，以激活JPA审核。我必须确保在指定 jpa：repositories 的行之前执行此操作。这看起来像：
I then needed to reference my "null object" AuditorAware implementation in an entry in my applicationContext to activate the JPA auditing. I had to make sure I did this before the line that specifies the jpa:repositories. This looks something like:
<bean id="auditorBean" class="your.package.subbed.here.NullAuditorBean"/>
<jpa:auditing auditor-aware-ref="auditorBean"/>
我还必须添加 orm.xml file，并且需要正式引用它作为我的 entityManagerFactory bean的属性，如下所示：
I also had to add an orm.xml file, and needed to formally reference it as a property of my entityManagerFactory bean, like so:
<property name="mappingResources">
<value>META-INF/orm.xml</value>
</property>
确保 META-INF / orm.xml 条目与您的编译输出一起存储（我的WAR在我的WAR下 WEB-INF / classes 。
Make sure this META-INF/orm.xml entry is stored with your compile output (mine is in my WAR under WEB-INF/classes.
记录中的 orm.xml 文件包含一些样板文件，可以在。
That orm.xml file, for the record, contained some boilerplate, which can be found in the answer to this related question.
这是我开始工作时需要做相当多的工作。您可能更喜欢以前的工作解决方案！
It was a fair amount of work when I got this working. You may prefer your previous working solution!
这篇关于Spring Data @CreatedDate注释对我不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！